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Dear Freesurfer experts,

Even though this problem has been raised in the archives, I was not able to find a specific solution to my problem.

I installed Freesurfer on a virtual machine which runs Ubuntu 18.04.4 (Host system: Windows 10). But it seems that Freesurfer is not installed properly. Upon running the installation test, I get the following errors:

1.) command line: cp $FREESURFER_HOME/subjects/sample-001.mgz . Error: cp: cannot create regular file './sample-001.mgz': Permission denied

2.) command line: mri_convert sample-001.mgz sample-001.nii.gz Error: mri_convert.bin sample-001.mgz sample-001.nii.gz $Id: mri_convert.c,v 1.226 2016/02/26 16:15:24 reuter Exp $ reading from sample-001.mgz... mghRead(/usr/local/sample-001.mgz, -1): could not open file

3.) command line: freeview Error: freeview.bin: error while loading shared libraries: libpng12.so.0: cannot open shared object file: No such file or directory.

My permissions are: drwxrwsr-x for freesurfer.

Any advice?

Many thanks!

/Ben